Field of the Invention
The present invention relates to a manufacturing method for a battery wiring module.
Related Art
In an in-vehicle battery pack to be connected to a power converter for driving a motor in a vehicle such as a hybrid car or an electric car, a battery module is configured that many battery cells are stacked in a manner of being alternatively reversed so that a positive electrode terminal and a negative electrode terminal are adjoined between the adjacent battery cells. Then, the electrode terminals of the adjacent battery cells are connected by a connection member such as a bus bar or the like, and thus a plurality of the battery cells are connected in series or in parallel.
In a case of assembling the battery module of the aforesaid configuration, it is necessary to connect between the electrode terminals via the respective connection members at plural portions. In view of this, a bus bar module is employed. The bus bar module is formed in a manner that a plurality of the connection members, arranged within a die according to the number of spaces among the electrode terminals to be connected, are integrally molded within insulation resin using an insert molding or the like.
In a case of connecting a plurality of the battery cells in series or in parallel, if battery characteristic such as a battery voltage is not uniform among the battery cells, degradation or breakage of the battery may be caused. Thus, in the in-vehicle battery pack, in order to stop charging or discharging before an abnormality occurs in a voltage between the respective battery cells, each of the bus bars is provided with a voltage detection wire for detecting a voltage of the corresponding battery cell.
In a bus bar module of a related art, the voltage detection wire adopts a configuration that a tip of a covered wire is peeled to expose a core wire, then a round terminal is crimped to the core wire, then the round terminal is fitted to an electrode terminal of a battery cell, and the round terminal is jointly fastened to the electrode terminal together with the connection member by a nut.
However, such the bus bar module has a problem that if the number of the voltage detection wires is large, an entire thickness of these wires becomes large and hence these wires are less likely bent. Also, as these wires are heavy as a whole, a wiring work of these wires becomes difficult. Further, the bus bar serving as the connection member is fitted to the positive and negative electrode terminals protruded from the battery cell. Also the round terminal crimped to the voltage detection wire is fitted to the electrode terminal and is jointly fastened to the electrode terminal together with the connection member by a nut. Thus, there arises a problem that a resistance value of a contact face between the bus bar and the round terminal becomes large to thereby cause a voltage drop therebetween.
In view of this, there has been proposed a high-voltage detection module device (bus bar module) for a battery pack which can easily wire to respective battery cells with a simple structure, and cause no voltage drop (for example, see a patent literature 1).
In this high-voltage detection module device for the battery pack, a plurality of bus bars are arranged at an insulation frame body combined with a battery pack body in a state of connecting prescribed positive and negative electrode terminals of the battery cell, then a flat cable is disposed in a region of the insulation frame body except this arrangement region, and conductive wires, separated by making notches in a specified shape between the respective conductive wires of this flat cable while leaving roots, are welded to the predetermined bus bars, respectively.
As the high-voltage detection module device for the battery pack thus configured is constituted of the insulation frame body, the plurality of bus bars and the flat cable, this device can be configured by a simple structure. Further, the high-voltage detection module device can be configured by simple works of arranging the bus bars at the insulation frame body, separating the respective conductive wires from the flat cable, and welding the conductive wires to the respective bus bars.